HPV induced cytologic changes of the cervix including malignancy have been reported to occur more commonly in women who are renal allograft recipients than in otherwise healthy women. A likely explanation for the reported discrepancy in the development of cervical dysplastic lesions is that latent HPV infection, acquired before organ transplantation, becomes activated under immunosuppression, and is therefore more easily detected and more difficult to control. Visible lesions associated with high risk HPV types are seen more commonly in patients with cell-mediated immune defects, suggesting that normal host immunity can usually control the proliferation associated with high risk HPV types better than that of the low risk types. Cervical malignancies progress more rapidly and are more difficult to manage in immunosuppressed women than in healthy women. There are similarities between the prevalence and HPV type distribution in genital lesions removed from female organ transplant recipients and that which we have observed in pregnant women when these populations are compared to normal women. This observation is consistent with the hypothesis that similar immunologic processes in transplant patients and pregnant patients regulate (or fail to regulate) HPV replication. Furthermore, because the immunosuppression associated with organ transplantation is prolonged while that of pregnancy is finite, the consequences of HPV infection are likely to be different. Populations of pregnant women and female organ transplant candidates can serve as models of genital HPV infection with accelerated natural histories, making a prospective study possible in a relatively short period of time. We will test three hypotheses: l) HPV DNA sequences are more often detected in genital tissue from immunosuppressed women (female organ transplant candidates) than in healthy nonpregnant women, 2) re-establishment of normal immune statues after pregnancy is associated with reduction in genital HPV detection, and 3) infection with both low and high risk HPV types has a different prognosis in immunosuppressed women than in pregnant women or nonpregnant healthy women.